Hydraulic transmission mechanism.



A. SUNDI'I. HYDRAULIC TRANSMISSION IIIECXI'IANISIII.

APPLICATION FILED MAR. IZ. 1914.

Patented Bec. 1'?, 19l8 lllllllll i Br f5 WITNESSES;

...UNITED STATES PATENT OFFICE.

l- AUGUST SUNDH, OIi` HASTINGS-UPON-HUDSON, NEW YORK, ASSIGNOR TO OTISELEVATOR'COMPANY, CORPORATION OF NEW JERSEY.

HYDRAULIC TRANSMISSION MECHANISM.

To alhvhonritjimq/ con'Camif:V Beit lmown that I, AUGUST SUNiiir, acitizen of the United States, residing in vI-IastingsupionHudso'n, inl'the county of 'Westchester and Sta-te of 11\ew York, have invented av"newand useful lmproveiiient in Hydraulicv 'lran'smission Mechanism,`of

which'tlie following'is a spfeciflcation.-

Myin'vention relates tov a system of control for hydraulic transmissionmechanism, and is particularly adapted to control mechanism-'comprisinga pump operated by; a

prime (mover such as an electric motor, said` pump supplying fluid to asecond motor which may be operatively connected to. any

mechanism that it is desired' to operate.v

One 0f theobjects of the invention is to desired -spee'd throughout theentire rangethereof.

Essentially the invention consists in the combination of a. drivingmember*comprising an electric motor, with hydraulic trans missionmechanismv of the character herein disclosed.' The characteristic of theelectric'y motor is'well known regarding the current consumption *ofthesame under load at starting, it being `a well known fact that thestarting current greatly exceeds the nor-' mal running current, 'andfurthermore the characteristic ot the lhydraulic transmission mechanismof the character herein disclosed. is also well known, in that thetorquel of the liuidmotor vai-ies inversely as the speed, or in otherwords, as the amount of fluid delivered thereto by the pump. The objectnow is yto start the electric motor and hydraulic?transmission mechanismsimultaneouslywhich by ni invention is effected by means of Sa manual yoperablecontroller,

and further to provide means for aut0` matically accelerating theelectric. and fluid motors sinniltaneously;'A thus the currentconsumption of the motor will be a minimum-and practically constantthroughout Specification of Letters Patent.

taneously therewith.

Patented Dec. 1r, 1918.

.ippnatip ined March 12, 1914. serial No. 824,086;

motor, the speed and torque of the Huid motor will be automaticallyvaried simul- The' accompanying drawingshows electrically operatedhydraulic' transmission mechanism, an automatic system of electricalcontrol therefor and a manually operable control arranged in accordancewith my invention.

The herein following description relating to the hydraulic transmissionmechanism, will be brief, since the saidmechanism fully shown anddescribed in detail, in my co-pending application, Serial Number764,994, filed May 2, 1913.

' The fluid rpressure motor F comprises a plurality of doubleactingcylinders whose pistons l, are connecte( to a common crank pin 2.A driven member comprises a cable sheave 3 which is keyed to the crankshaft and is `adapted to receive the hoisting cables of an elevator orother hoist, although .if desired the sheave S-may be replaced by a beltpulley, gear, or other device whereby power may be transmitted from thecrank shaft to any desired power consuming device.

The pump is adapted to deliver fluid under pressure t0 the fluid motorF. The stroke of the pump plungers 5, is controlled by means of atilting head 6, carried upon a shaft 7 in anti-friction bearings 8. Theright hand end of the'tilting head is provided on its innercircumference with a ball race t which is secured in place by means of aring 9 and coacting ball race 9 carried by a ring 13, which isconcentric with the shaft 7, but is adapted to be shifted to aneccentric position with respect to the shaft 7 by means of a slidinwedge 1Q. The latter is arranged to sli e longitudinarlly in a slot inthe shaft by means of a lever 11, which is bifurcated in its lower endand has a pair of oppositely disposed pins` which enter acircumferentialAgroove in the part 12, which is integral with the key 'orwedge 10.Bypthis arrangement the eccentricity of the ring y13 can be varied fromzero to a maximum in either direction, by sliding 'the wedge lengthwiseof the shaft by means of the lever 11. 'The length of the stroke of theplungers will the periods of start-ing and acceleration to full speedand vice versa, and throughout the entire ranges of speed. of theelectric-r obviously depend upon the amount of tilt chambers 36 pivotedat 37.

or inclination given to the tilting head b v means ot the wedge, andsince this "factor may be varied at will, the output ot' the pump may becontrolled within prede'- termined limits, or it' desired, the pump maybe arranged to reverse the direct-ion ot flow of fluid by moving thewedge in a right hand direction past center.

A rotary valve l-l is operated from the pump shaft and is adapted tohave a sliding movement thereon. This valve directs the fluid betweenthe pump and fluid motor.

'Means for imparting a sliding movement ot the valve 14 upon the shaft 7comprises a grooved collar 15, provided on either lateral face' .withball thrust bearings which are secured to or carried upon the valve. 'Apivoted lever 16 has a pin on it which rides in the groove on saidcollar, the arrangement being such thatI the valve may be shit'ledlongitudinally of the shaft b v means ot' the lever 16. The latter isprovided .with a pin 17 at its other end, which pin is adapted to ridein a. cam slot 1S formed in the cam 19. The lever 11 by which the wedge10 is shifted is also provided with a pin 20 which rides in a cam slot21 in the cam Both of the cams 1S) and 22 are .secured to a shaft23,-c-arrying a pinion 24. Thus it will be seen that by rotation of thepinion` the stroke of the pump plungers and shifting of the valve iseffected simultaneously.

The pinion :2l is rotated by means of' a, fluid actuated piston having arack 26 formed integrally or otherwise connected with the piston rod 27.A pilot valve 28 directs 'the fluid from a supply pipe 2) into 30 or 31,above and below the piston 25. Stems 32 and 33 of the pilot valve andpistons respectively, are connect-ed in the usual manner by a lever 34,which is con-A nected through another lever 35 to an arm A plurality ofelectromagnets A, A', A2, A3, A4, are opera-tively connected` to the arm36, at the right of the pivot point and are adapted to operatesuccessively in the order named to effect a graduated movement of thepilot valve 28 in a downward direction; and likewisea plurality ofelectromagnets B, B', B2, B3, B4, are operatively connected to therocker arm 36, at the left of the pivot point and are adapted to operatesuccessively in the order named -to effect a graduated n'lovenlent ofthe pilot valve 28 in an upward direction.

It will now be seenl from the above dej scription that the inclinationgiven to thel tilting head by means of the wedge 10 is controlled withinpre-determined limits by the electromagnets A. A'. etc., and B, B', etc.The electromagnets A, A', etc.control the, movement of the wedge in aright hand direction past center, and the electromagnets B. B', etc.,control the movement of the. .wedge in a left hand direction past.center.

These magnets of course likewise control the movement of the valve 14;also.

A prime mover such as. anelectric motor M, is adapted to drive the pumpshaft 7, said motor being preferably a shunt wound motor. A sectionalresistance 38 in the motor circuit is controlled by a plurality ofelectromagnetic switches C, C', C2, C3, and C4. As herein shown Iprovide, five switches for controlling the said resistance, but anydesired number may be used, according-to the amount of resistance usedand the desired refinement of operation. These switches Vare providedwith windings 39, l0, ll, l2 and 43, one of the. terminals of eachwinding running to a manually operable switch D, ther other terminals ofsaid .windings being connected to a connnon conductorfkl, which isconnected at a suitable point. in the resistance. 'Vlie manuallyoperable switch l) comprises a rever 44, which actuates a Contactsegment t5, said segment being adapted to engage the contacts 4,6 whenthe lever is moved to the left, and contacts 47 when moved t0 the right.

The cores 48, of the windings 39, ll), l1. etc., are adjusted in a wellknown manner as by means of suitable .adjusting membersA t9 to effectthe successive operation of' the switches C, C', etc., in the ordernamed` when the circuits for the ,windings 3f). 40. -l1,- etc., areclosed simultaneously, or in other words when thelever 44 is moved toits full left or. right hand position. 'The closing of each switch C,C', etc., effects the cutting out of a portion of the resistance 3S.thereby effecting a correspomling increase in the speed of the motor,7until the last section is cut out, whereupon the motor will run at fullspeed.

Switches J, J', J2, J3, and J", are also controlled by the cores of thewindings 39, 40, etc. These switches control the circuits for theelectro-magnets :L A', etc., and B, B. etc., dependent on the directionof movement of the hand lever 44, so thatI the successive operation ofsaid electro-magnet is effected i simultaneously with the successiveoperation of the switches C, C', etc., wlnch control the p 'resistance38.

One of the terminals of each of the windings of the electromagnets A,A', etc., are. connected to contacts 50, 51, 52, 53 and 5l, associatedwith the switches J, J', etc., the other terminals thereof beingconnected to a common 'conductor 55 connected to one of the contacts 46.One of the terminals o f each of the windings B, B', etc., are connectedin parallel with the terminals of the windings A, A', etc., which arecontrolled by the switches J, J', etc., the other terminals thereofbeing connected to a common conductor 56, which is connected to one ofthe set of contacts 47.

lt is to be here pointed out that` the electric motor is adapted to runin one direction only, since a reversal of the driven member 4 iseffected by reversing the direction of flow of fluid between the pumpand fluid motor, this operation being controlled from the switch D.

An electromagnetic mainline lswitch H, is controlled from the'switch D.G is a knife switch, connecting the source of current supply designated-iand With the electromagnetic lswitch.

The operation will now be described; the parts as shown are in normalposition at rest. By moving the lever 44 to the right; so that thesegment 45 spans the first three contacts of the set 47, a circuit isestablished for the winding of the main line switch as follows:` fromthe -lconductor, through conductor 57 to conductor 58, which is a commonconductor connecting with the first contact of each of the sets 47 and46, through the first contact to segment 45, to

i the third contact, conductor 59, through the winding of the switch H,conductor 60, to line. The switch H will now close, thereby closing acircuit for the motor, which circuit includes all of the resistance 38.The motor will now start up at slow speed. lFurther movement of thesegment into engagement with the fourth contact closes a cir'- cuit forthe winding 39, as follows: from conductor 58 to first contact, contactsegment 45', through the'fourth contact to conductor 61 which is alsoconnected to the fourth contact of the sety46, conductor 62, through thewinding 39, to the conductor 44 connected to the resistance 38. Thewinding 39 now receiving current effects the closing of the switches Cand J. The switch C now being closed, cuts out the first section of theresistance 38, and effects an increase in the speed of the motor M, butit is to be noted that the switch J closes a circuit for'- the windingof the electroinagnet B, the circuit therefore being as follows: fromconductor 58 through the first cont-act to segment 45, "to secondcontact, conductor 56, through the winding of the electromagnet B,conductor 63, throu'gh switch J, conductors 64 and 65 to main. Theelectromagnet B y now receiving current, will rock the arm 36v source ofsupply.

a small amountin a counter-clockwise direction and effect a small amountof movement of the pilot valve in an upward direction thereby connectingthe chamber 30 with the y A small amount of fluid will now flow into thechamber 30 and effect a downward movement of the piston 25 apredetermined amount, which effects the rotation of the cams 22 and 19 apredetermined amount in a counter clockwise direction, thereby movingthe wedge. l0 a predetermined amount to the left of-ccnter to tilt thehead from a concentric to'an' eccentric' position7 whereupon the samewill now operate and effect the reciprocation of all the pump plungersin their respective cylinders..

amount of' current to operate the pump, but y a powerful torque lwill bedelivered by the fluid motor, since as before stated herein, the torqueof the Huid motor varies inversely as the speed, or in other words, asthe amount of fluid delivered thereto by the pump. Now upon thecontinued movement of the lever 44 to engage the remaining contacts, theremaining switches C', C2, etc., and J', J2, etc., will closesuccessively in the order named, thereby cutting out the remaining stepsof resistance,lthus causing a gradual acceleration of the electric motorto full speed, and simultaneously as each of the remaining steps ofresistance are cut out., a predetermined increase in the stroke of thepumpplungers is effected, thereby increasing the quantities of fluiddelivered by the pump tothefluid motor, but at proportionatelydecreasing pressures. Thus the fluid motor will accelerate to fullspeed, depending of course on the load thereon.v

Thus it will Abe seen that the electric motor and fluid motor arestarted practically simultaneously, and the automatic variation in thespeed and torque of the two motprs throughout the entire range from zeroto maximuin'is effected simultaneously. It will thus -be seen that apowerful torque is delivered by the fluid motor in starting whichtorquey decreases as the speed increases, and furthermore a minimumamount of current is consumed by the electric motor. which current willbe practicallyconstant through-v out the entire range of speed ofthemotor.

It is to be further noted that the rate of speed of the electric motormay exceed that ofthe fluid motor, said speed of the fluid to theirnormal positions.

It will hehere noted that the operation of the electric motor and fluidmotor can lbe maintained at any predetermined intermediate speed betweenthe minimum and maxi-V mum, by means of the lever 44, and furthermore,if said lever is moved either to its full right or left hand position,the electromagnetic switches will operate successively the arm 36 andthe pai-ts connected therewith of' operation, etc., of the in a wellknown manner to cut out the scctionarl resistance 38, since the commonconductor 44 of the windings 39, l0, etc., is connected at a point onsaid resistance, and the other ends thereotbeing connected through theswitch D to the main and thus the energization otl said windings dependson the couliter-electroniotive force ot' the rotating armature.

The operation ot' the di'iveii member Jr in a reverse direction iseffected by moving the lever ll to the lct't to engage the contacts lli.ln this operation the direction of rotation of' the electric motor isunchanged. but the` electromagnets A, A', etc., will now operate thepilot valve "ZS in a downward direction, thereby effecting a movement ofthe wedge l() in a right hand direction past center and resulting inreversal of' fluid bctwcen the pump and fiuid motor. The mode variousparts by moving the lever 7H to the left is similar to that justdescribed by moving the lever to the right, and therefore docs notnecessitate further explanation. l,

It is to be distinctly understood that my invention is broadlyapplicable to the various types of variable speed transmission mechanismhaving a torque and speed characteristic which vary in inverse ratio,and said mechanism being adapted to be driven by -a prime mover, and itis to be further understood that although I show herein a hydraulictransmission system, I wish not to be limited in the application of myinvention to the particular power transmission system herein disclosed.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is 1. A driving and driven member, power transmission mechanisminterposed between said members, means for starting and automaticallyaccelerating thedriving member from vzero to maximum under variableloads, and means for starting and automatically accelerating the powertransmission mechanism simultaneously with the driving inember.

2. A driving and driven member, power transmission mechanism interposedbetween said members, manually operable means, and means controlledthereby for starting and automatically accelerating the driving meniberand power transn'iission .mechanism simultaneously.

3. The combination with fluid power transmission mechanism, a primemover for driving the saine, means for starting and ac-' celex-ating theprime mover, and means controlled by the first named means for effectingthe operation of the hydraulic-transmission mechanism simultaneouslywith the prime mover. V

4. The combination with 'fluid power transmission mechanism, an electricmotor j" for driving the mechanism, and means for controlling saidelectric motor and Huid power mechanism to etl'ect the starting.stopping, and acceleration thereof simultaneously throughout theirentire range of speeds.

5. The combination with fluid power transmission mechanism, an electricmotor for driving the saine, means for starting andautoniaticallyaccelerating the electric motor from zero to maximum under variableloads, and means f'or starting and automatically accelerating the fiuidpower transmission mechanism sinniltaneously with the electric motor.

(l. The combination 'with fluid power transmission mechanism, an clectifmotor for driving the same, a manually operable member, and meanscontrolled thereby for starting-and automatically accelerating theelectric motor, and fluid power transmission mechanism simultaneously.

7. The combination with Huid power transmission mechanism, anon-reversing electric motor, means for starting and automaticallyaccelerating the electric motor from zero to maximum under variableloads, and means for starting-the fluid power transmission mechanism iiieither direct-ion and automatically accelerating the samesiniultaneously with the electric motor.

Y8. The combination with Huid power transmission mechanism, an electricmotor for driving the same, means for connecting the motor with a.source of power supply, electro-responsive means for accelerating saidmotor in proportion to the load thereon, and means dependent on theacceleration of.'- the electric motor for controlling the accelerationot' the fluid power transmission mechanism.

9. The combination with fluid power transmission mechanism, an electricmotor for driving the same, means t'or connecting the motor with asouice of current supply, electromagnetic means for automatically'varying the speed of the elect-ric motor, and

electrically controlled means for ,automatically varying the speed andtorque of the' fluid power transmission mechanism simultaneously withthe variation of the electric motor speedf 10. The combination withfiuid power transmission mechanism, an electric motor for driving thesame, a. manually operable 'controller for connecting said motor Wit-h asource of power supply, electro-responsive mechanism for automaticallyvarying the speed of the electric motor, and means controlled by saidelectro-responsive means for starting and automatically varying thespeed Vof' the fluid power transmission mechanism simultaneously withthe electric motor.

11. The combination with a fluid pressure motor,'pumping mechanismadapted to supmeeste y ply said motor with fluid under pressure, anelectric motor for driving the pumping; mechanism, means dependent onthe load on the motor for starting and eti'ecting a variation in thcspeed of the electric motor, and means for starting and ell'ecting' avariation in the speed oli the fluid pressure motor simultaneously withthc electric motor.

l2. rl`hecoinhination with a fluid pressure motor, pumping mechanismadapted to supply said motor with fluid under pressure, an electric:motor for driving the pumping mechanism, means tor connecting;v theelectrioniotor with a source ot current supply, electro-responsive meansfor etlectingr a va* riation in'spced ot the electric motor, and

electrically controlled mechanism dependenton the variation in the speedol tlie electric motor, for automatically varying the speed and torqueof the fluid pressure motor, by varying the quantity of fluid deliveredby thc pumping mechanism.

123. The combination with a lluid pressure motor, pumping mechanism forSupplying said motor with tluid under pressure, an electric motordriving` the pumping mechan nisni, means for starting and automaticallyellcctinev a variation in the speed of the electric motor from zero tomaximum under variable loads, and means for starting and automaticallyvarying the speed and torque of the fluid motor -in inverse ratio, simultaneously with the electric motor, by varying the output of the pumpingmechanism.

ll. 'lhc combination with a 'fluid pressure motor, pumping; mechanismfor eupplying said motor with Huid under pressure, an electric motor fordrivingv the pumping.; mechanism, means for starting and automaticallyeffecting a 'variation in the speed of the electric motor, and means forstarting and automatically i-*arying the speed and vtorque of the fluidmotor ininverse ratio,

simultaneously with the ot' the electric motor.

l5. The combination with a. fluid prcssure motor, pumping mechanism 'forsup* plying said motor with fluid under pressure, an electric motor fordriving the pumping mechanism, means for connecting` the electric motorwith a source ot current supply, electro-responsive means tor varyingthe speed portion to the load thereon, and means dependent on thevariation in speed ot the variation in speed V electric motor foreffecting a variation in the speed and torque of the fluid motor ininverse ratio, by varying' the quantity or fluid delivered to the fluidmotor.

of the electric motor in time pio sive means controlled by said manualcontroller for automatically varying the Speed of the electric motor,and means controlled by said manual controller, but dependent .on thevariation in speed of the electric motor, for automatically varyingthespeed and toroue' of the fluid motor iii-inverse ratio.

l i. l'he combination with a i'luid pressure motor., a pump for.supplying said inotor with tluidunder pressure, an electric motor. meansfor startingl and 'automatically accele ating the electric motor fromzero to maximum in time proportion to the lo'adifon the fluid motor, andmeans for starting and automatically accelerating the luid 'motorsimultaneously with the electric motor, by varying the fluid output ofthe pump,

whereloy the speed and torque of the fluid motor will.- vary in. inverseratio.

18. The combination with` a fluid pressure motor, a pump for supplyingfluid under pressure thereto, an electric motor for drivi ing the pump,a manually operable controller, an electro-magnetic switch controlledthereby for connecting the. electric motor with a source ofnoui'rentsupply, electro-responsive means controlled oy said controller forautomati 'ally' accelerating the electric motor from zero to maximiunand in time proportion to the load on thc tluicil motor, andelectrically operated mechanisii.- controlled said elect-rmresponsivemeans. for automatically varying the output of the ilnimpingi,-mechanism simultaneously with the variation in speed of the electricmotor. if). The combination with a lluid pressure motorA` a pump forsupplying fluid under pressure thereto, an electric motor operativelyconnectedto the pump, means for starting` and automatically acceleratingthe electric motor, means lor 1varying; the output of the. pump, andelectro-responsive mechanismy for controlling the last. named means toeil'ect a variation in the output. of the pump, simultaneously with a.variation in the speed of the electric motor.

lirtesiimony whereof, l have. signed .my name to this specification inthe pre-sence ot' two subscribing witnesses.

AUGUST llil'r.

Vilitnesses:

WALTER C. Sriisinc, JAMES G. Barnum,.-

